Investigation of the D614G Mutation and Antibody-Dependent Enhancement Sequences in Indonesian SARS-CoV-2 Isolates and Comparison to Southeast Asian Isolates
Reviany V. Nidom, Setyarina Indrasari, Irine Normalina, Muhammad K. J. Kusala, Arif N. M. Ansori, Chairul A. Nidom
Introduction: SARS-CoV-2 is a rapidly spreading virus that poses a major burden on global human health and the economy. Therefore, it is essential to develop COVID-19 vaccines. Vaccine construction might not be easy, as a consequence of mutations and antibody-dependent enhancement (ADE). Objective: We first reported the D614G mutation and ADE sequences in Indonesian SARS-CoV-2 isolates and compared these isolates to those from other Southeast Asian countries. Methods: In this study, we extracted the SARS-CoV-2 genome of 40Indonesian isolates from the GISAID EpiCoV database and the Wuhan-Hu-1 isolate (reference sequence) from GenBank, NCBI. We used BioEdit v7.2.5 to identify the D614G mutation and ADE sequences in the spike protein. Then, we rendered the spike protein usingthe SWISS-MODEL web server and PyMOL v2.4. Results: We identified the D614G missense mutation in 23Indonesian SARS-CoV-2 isolates and isolates from six other Southeast Asian countries. In addition, we identified the ADE sequence 611LYQDVNC617in the Wuhan-Hu-1 isolate, which had changed into 611LYQGVNC617in recent mutated isolates. Conclusion: We conclude that the D614G mutation might affect ADE activities. A rapid but cautious approach to the vaccine development and other therapies developed for COVID-19 seems needed until we have more data on the risks of the D614G mutation and ADE. However, further studies including in vitroand invivoassessmentsare relevant for validation of these results.